Source code for jaxley.connect

# This file is part of Jaxley, a differentiable neuroscience simulator. Jaxley is
# licensed under the Apache License Version 2.0, see <https://www.apache.org/licenses/>

import numpy as np


def is_same_network(pre: "View", post: "View") -> bool:
    """Check if views are from the same network."""
    is_in_net = "network" in pre.base.__class__.__name__.lower()
    is_in_same_net = pre.base is post.base
    return is_in_net and is_in_same_net


def sample_comp(cell_view: "View", num: int = 1, replace=True) -> "CompartmentView":
    """Sample a compartment from a cell.

    Returns View with shape (num, num_cols)."""
    return np.random.choice(cell_view._comps_in_view, num, replace=replace)


[docs] def connect( pre: "View", post: "View", synapse_type: "Synapse", ): """Connect two compartments with a chemical synapse. The pre- and postsynaptic compartments must be different compartments of the same network. Args: pre: View of the presynaptic compartment. post: View of the postsynaptic compartment. synapse_type: The synapse to append """ assert is_same_network( pre, post ), "Pre and post compartments must be part of the same network." pre.base._append_multiple_synapses(pre.nodes, post.nodes, synapse_type)
[docs] def fully_connect( pre_cell_view: "View", post_cell_view: "View", synapse_type: "Synapse", random_post_comp: bool = False, ): """Appends multiple connections which build a fully connected layer. Connections are from branch 0 location 0 of the pre-synaptic cell to branch 0 location 0 of the post-synaptic cell unless random_post_comp=True. Args: pre_cell_view: View of the presynaptic cell. post_cell_view: View of the postsynaptic cell. synapse_type: The synapse to append. random_post_comp: If True, randomly samples the postsynaptic compartments. """ # Get pre- and postsynaptic cell indices. num_pre = len(pre_cell_view._cells_in_view) num_post = len(post_cell_view._cells_in_view) # Pre-synapse is at the zero-eth branch and zero-eth compartment. pre_rows = pre_cell_view.scope("local").branch(0).comp(0).nodes.copy() # Repeat rows `num_post` times. See SO 50788508. pre_rows = pre_rows.loc[pre_rows.index.repeat(num_post)].reset_index(drop=True) if random_post_comp: global_post_comp_indices = ( post_cell_view.nodes.groupby("global_cell_index") .sample(num_pre, replace=True) .index.to_numpy() ) # Reorder the post comp inds to tile order (pre indices are repeated so here tile needed) global_post_comp_indices = np.reshape( global_post_comp_indices, (num_pre, num_post) ).T.flatten() else: # Post-synapse also at the zero-eth branch and zero-eth compartment global_post_comp_indices = ( post_cell_view.nodes.groupby("global_cell_index").first()[ "global_comp_index" ] ).to_numpy() to_idx = np.tile(range(0, num_post), num_pre) global_post_comp_indices = global_post_comp_indices[to_idx] post_rows = post_cell_view.nodes.loc[global_post_comp_indices] pre_cell_view.base._append_multiple_synapses(pre_rows, post_rows, synapse_type)
[docs] def sparse_connect( pre_cell_view: "View", post_cell_view: "View", synapse_type: "Synapse", p: float, random_post_comp: bool = False, ): """Appends multiple connections which build a sparse, randomly connected layer. Connections are from branch 0 location 0 of the pre-synaptic cell to branch 0 location 0 of the post-synaptic cell unless random_post_comp=True. NOTE: This function does not generate sparse random connectivity with random graph generation methodology, cells may be connected multiple times and p=1.0 does not fully connect. Args: pre_cell_view: View of the presynaptic cell. post_cell_view: View of the postsynaptic cell. synapse_type: The synapse to append. p: Probability of connection. random_post_comp: If True, randomly samples the postsynaptic compartments. """ # Get pre- and postsynaptic cell indices. pre_cell_inds = pre_cell_view._cells_in_view post_cell_inds = post_cell_view._cells_in_view num_pre = len(pre_cell_view._cells_in_view) num_post = len(post_cell_view._cells_in_view) num_connections = np.random.binomial(num_pre * num_post, p) pre_syn_neurons = np.random.choice(pre_cell_inds, size=num_connections) post_syn_neurons = np.random.choice(post_cell_inds, size=num_connections) # Sort the synapses only for convenience of inspecting `.edges`. sorting = np.argsort(pre_syn_neurons) pre_syn_neurons = pre_syn_neurons[sorting] post_syn_neurons = post_syn_neurons[sorting] # Pre-synapse is at the zero-eth branch and zero-eth compartment. global_pre_indices = pre_cell_view.base._cumsum_ncomp_per_cell[pre_syn_neurons] pre_rows = pre_cell_view.base.nodes.loc[global_pre_indices] # Sample the post-synaptic compartments if random_post_comp: # Filter the post cell view to include post-synaptic neurons post_syn_view = post_cell_view.nodes[ post_cell_view.nodes["global_cell_index"].isin(post_syn_neurons) ] # Determine how many comps to sample for each post-synaptic neuron unique_cells, counts = np.unique(post_syn_neurons, return_counts=True) n_samples_dict = dict(zip(unique_cells, counts)) sampled_inds = post_syn_view.groupby("global_cell_index").apply( lambda x: x.sample(n=n_samples_dict[x.name], replace=True) ) global_post_comp_indices = sampled_inds.global_comp_index.to_numpy() post_rows = post_cell_view.nodes.loc[global_post_comp_indices] else: # Post-synapse also at the zero-eth branch and zero-eth compartment global_post_indices = post_cell_view.base._cumsum_ncomp_per_cell[ post_syn_neurons ] post_rows = post_cell_view.base.nodes.loc[global_post_indices] if len(pre_rows) > 0: pre_cell_view.base._append_multiple_synapses(pre_rows, post_rows, synapse_type)
[docs] def connectivity_matrix_connect( pre_cell_view: "View", post_cell_view: "View", synapse_type: "Synapse", connectivity_matrix: np.ndarray[bool], random_post_comp: bool = False, ): """Appends multiple connections according to a custom connectivity matrix. Entries > 0 in the matrix indicate a connection between the corresponding cells. Connections are from branch 0 location 0 of the pre-synaptic cell to branch 0 location 0 of the post-synaptic cell unless random_post_comp=True. Args: pre_cell_view: View of the presynaptic cell. post_cell_view: View of the postsynaptic cell. synapse_type: The synapse to append. connectivity_matrix: A boolean matrix indicating the connections between cells. random_post_comp: If True, randomly samples the postsynaptic compartments. """ # Get pre- and postsynaptic cell indices num_pre = len(pre_cell_view._cells_in_view) num_post = len(post_cell_view._cells_in_view) assert connectivity_matrix.shape == ( num_pre, num_post, ), "Connectivity matrix must have shape (num_pre, num_post)." assert connectivity_matrix.dtype == bool, "Connectivity matrix must be boolean." # Get pre to post connection pairs from connectivity matrix from_idx, to_idx = np.where(connectivity_matrix) # Pre-synapse at the zero-eth branch and zero-eth compartment global_pre_comp_indices = ( pre_cell_view.nodes.groupby("global_cell_index").first()["global_comp_index"] ).to_numpy() pre_rows = pre_cell_view.select(nodes=global_pre_comp_indices[from_idx]).nodes if random_post_comp: global_to_idx = post_cell_view.nodes.global_cell_index.unique()[to_idx] # Filter the post cell view to include post-synaptic neurons selected post_syn_view = post_cell_view.nodes[ post_cell_view.nodes["global_cell_index"].isin(global_to_idx) ] # Determine how many comps to sample for each post-synaptic neuron unique_cells, counts = np.unique(global_to_idx, return_counts=True) # Sample the post-synaptic compartments n_samples_dict = dict(zip(unique_cells, counts)) sampled_inds = post_syn_view.groupby("global_cell_index").apply( lambda x: x.sample(n=n_samples_dict[x.name], replace=True) ) global_post_comp_indices = sampled_inds.global_comp_index.to_numpy() else: # Post-synapse also at the zero-eth branch and zero-eth compartment global_post_comp_indices = ( post_cell_view.nodes.groupby("global_cell_index").first()[ "global_comp_index" ] ).to_numpy() global_post_comp_indices = global_post_comp_indices[to_idx] post_rows = post_cell_view.select(nodes=global_post_comp_indices).nodes pre_cell_view.base._append_multiple_synapses(pre_rows, post_rows, synapse_type)